1. Field of the Invention
This invention relates to a newly disclosed frontal attachment having a retractable needle that is attachable to conventional medical devices such as syringes. The invention relates more particularly to a medical device comprising in combination a needle, needle positioner, needle retraction mechanism, and a syringe engaging member with a retraction tube. The subject device has a needle retraction mechanism that is activated by pinching action and retracts the needle from a patient and propels it into a retraction tube that is part of the hub assembly.
2. Description of Related Art
Conventional syringes comprising a generally cylindrical barrel, a fixed needle projecting forwardly from the barrel, and a plunger slidably disposed inside the barrel through an opening in the rear of the barrel are well known. More recently, syringes have been made with a luer connector on the front of the barrel to which a needle hub is attachable to allow needles of different gauges or sizes to be used with a commonly configured barrel.
Even more recently, in an effort to control the spread of blood-borne pathogens and the incidence of contamination by contact with either exposed needles or bodily fluids, syringes having fixed or changeable needles have been designed to embody various “safety” elements. Such “safety” elements should desirably include a retractable needle, but many products marketed as having “safety” elements include, for example, covers or guards that are manually operated by medical personnel administering an injection to shield or cover the needle tip following removal of the needle from a patient.
Some previously disclosed needle retraction systems without changeable needles are activated either manually or automatically by application of a force upon completion of an injection to force the needle and needle tip back inside a retraction chamber. The only known syringe having a changeable, retractable needle does not have a conventional luer lock connection, and the retraction mechanism is activated by the application of a forwardly directed force to the plunger handle following removal of the needle from a patient, thereby exposing the needle and also exposing the user to the risk of needle-stick injury.
Although many advancements in syringe technology have been made in recent years, a frontal attachment device is needed that can be used with a standard syringe having a conventional luer lock connector, that offers the advantages of a changeable needle in combination with the advantages of a retractable needle providing sufficient retraction force to retract the needle while inserted into a patient, and that can be activated simply and easily by the application of a pinching force.